How to control Android back stack

Question

Say I have

A-> B-> C-> D-> E

In the Android feedback stack. I want to be able to return to one of the following:

A->B->C A->B A 

How can i achieve this? We hope you don’t press a button by pressing a button.

Answer 1

Using the image and information from the official developers page for Android tasks and the back stack , you can see that of all the other ways to start an Activity, you can ensure this behavior only by using FLAG_ACTIVITY_CLEAR_TOP in your Intent FLAG_ACTIVITY_CLEAR_TOP .

Your regular return button works as follows:

But when you specify this flag, you will get the behavior you need as shown in this source :

consider a task consisting of actions: A, B, C, D. If D calls startActivity () with an intent that resolves the activity component B, then C and D will be completed, and B will receive the given Intent, as a result of which the stack will now be: A, B.

Answer 2

Use the flag FLAG_ACTIVITY_CLEAR_TOP .

 Intent a = new Intent(this, A.class); a.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(a); 

Answer 3

Actually, to go to the action of your choice, you must use the up navigation, which is used on the action bar:

 /** used to handle the "up" button on the action bar, to go to the defined top activity as written on the manifest */ public static void goUpToTopActivity(final Activity currentActivity) { final Intent intent = NavUtils.getParentActivityIntent(currentActivity); intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP); NavUtils.navigateUpTo(currentActivity, intent); } 

to use it, you must set the action in the manifest that this function should use (or you can of course set it yourself by changing the code):

if you use actionBarSherlock, for every action you want to open, use:

 <meta-data android:name="android.support.PARENT_ACTIVITY" android:value="com.your_app.activities.MainActivity" /> 

if you use the android framework (if your version of minSdk is API 16 and above), use " parentActivityName ".

Answer 4

Suppose you use Intent to jump to another action.

 Intent i = new Intent(A.this,B.class); startActivity(i); 

this code will take you to action “B”, and when you press the back button, it will take you back to “A”. If you do not want to return to activity "A", you can use ...

 Intent i = new Intent(A.this,B.class); i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK); startActivity(i); 

For more information about Back Stack on Android, follow this link: http://developer.android.com/guide/components/tasks-and-back-stack.html